JP2007202830A - Dishwasher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure a disinfecting performance without prolonging washing time more than needed in low temperature washing. <P>SOLUTION: The dishwasher includes: a washing tub storing the dishes; a hot water heater for heating washing water; a pump for spraying the washing water to the dishes; a blowing fan for discharging air inside the washing tub; and a controller for controlling the hot water heater, the pump and the blowing fan and making the dishes be washed, rinsed and dried according to a prescribed washing mode. Washing modes include a standard washing mode and a low temperature washing mode. The low temperature washing mode includes a disinfecting process 32 for stopping the operation of the pump, making the hot water heater perform heating so as to elevate the temperature of the washing water to a prescribed temperature and disinfecting the dishes after a washing process 31 for washing the dishes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a dishwasher, and more particularly to a technique for improving sterilization performance in low-temperature washing for washing dishes having a low heat-resistant temperature.

A plurality of different cleaning modes are prepared in advance in the dishwasher, and the user selects a desired mode from among them to perform dishwashing (for example, Patent Document 1).
JP 2003-61890 A

  Among the various dish washing modes, low temperature washing is performed by washing at a lower temperature than the standard washing mode in order to wash items with low heat resistance, such as plastic dishes. There is a mode. In this low temperature cleaning mode, the temperature of the cleaning water is as low as around 55 degrees compared to 70-80 degrees in the normal cleaning mode. For this reason, in the low temperature washing | cleaning, the microbe elimination performance is weak, and measures, such as washing | cleaning more than needed, were needed for ensuring the sanitary surface.

  Therefore, an object of the present invention is to ensure the sterilization performance without increasing the cleaning time more than necessary in the low temperature cleaning.

  According to the present invention as set forth in claim 1, a dishwasher for washing, rinsing and drying stored tableware is a washing tank for storing tableware, heating means for heating washing water, and washing the tableware. A cleaning pump for spraying water, a blower fan for discharging the air in the cleaning tank, and controlling the heating means, the cleaning pump and the blower fan to wash the dishes according to a predetermined washing mode; And control means for performing rinsing and drying. The predetermined cleaning mode includes a first cleaning mode and a second cleaning mode in which the temperature of the cleaning water is lower than that in the first cleaning mode, and the second cleaning mode includes the tableware. After the cleaning, the control means stops the operation of the washing pump, and then the heating means is heated so that the washing water temperature rises to a predetermined temperature to disinfect the dishes. Has a fungal process.

  Thereby, since dish washing is first performed at a low temperature, it is possible to surely wash a plastic container or the like that can be washed only at a low temperature. Furthermore, after the cleaning, the cleaning pump is stopped, and a sterilization process is performed in which the sterilization is performed by increasing only the atmospheric temperature in the cleaning tank in a state where the direct spraying of the high temperature cleaning water is stopped. As a result, it is possible to surely enhance the sterilization ability by causing the hot gas to touch the tableware while preventing the plastic container or the like from being deformed by heat. Therefore, the sterilization performance can be improved without making the washing time longer than necessary. In more detail about this point, since air has a smaller heat capacity than tableware, even if air heated to a high temperature comes into contact with tableware having a temperature lower than that of air, it is not possible to quickly raise the temperature of the tableware. On the contrary, when it comes into contact with the tableware, it is cooled to a temperature close to the tableware. Therefore, the temperature of the tableware is not increased so as to cause the tableware to be thermally deformed by the present sterilization control in which the tableware is brought into contact with hot air for a limited time. However, since the temperature is high until the air touches the surface of the tableware, a great effect can be expected for heat sterilizing the tableware surface.

  According to the second aspect of the present invention, the blower fan has at least a plurality of operation characteristics with different blow modes, and in the sterilization step, the control means performs intermittent operation with the lowest blowing ability by the blower fan. Configured to do.

  Thereby, since the gas convects in the washing tank with the driving of the blower fan, the hot gas can be surely and evenly touched to the tableware, and higher sterilization performance is ensured. In addition, since the temperature distribution in the washing tank can be made uniform by the air flow, the low temperature portion is eliminated, and the sterilization performance can be ensured more reliably, and conversely, it occurs when there is a high temperature portion above a predetermined level due to variation in the temperature distribution. The influence of heat on the low-temperature heat-resistant container such as plastic can be suppressed, and the deformation of the tableware can be surely prevented. Furthermore, since the air flow is not strong and gentle because the blower fan has low air blowing capability, the hot air is concentrated strongly and does not collide with the low-temperature heat-resistant container. Can be sterilized.

  According to the third aspect of the present invention, in the second cleaning mode, the cleaning water temperature when cleaning the dishes is 60 degrees or less, and the cleaning water temperature in the sterilization step is 61 degrees or more and 70 degrees. It is as follows.

  As a result, in the cleaning process in which the cleaning water is directly sprayed, the cleaning water temperature is set to 60 ° C. or less, so that the low temperature heat resistant container can be reliably cleaned by strong spraying of the cleaning water without causing thermal deformation or the like. On the other hand, in the sterilization process, the washing water temperature is increased to a high temperature of 61 ° C. or more and 70 ° C. or less. However, since the washing pump is stopped and the washing water is not sprayed, the high temperature washing water is directly applied to the low temperature heat-resistant container. High sterilization performance can be ensured without causing deformation even with tableware having a low heat-resistant temperature because it is not touched and does not give an impact force.

  According to this invention of Claim 4, in the said microbe elimination process, the said control means controls the said heating means which heats the said wash water so that the air in the said washing tank may become below predetermined temperature. I have to.

  According to this, when sterilization is performed by raising the temperature of the washing water to increase the ambient temperature in the washing tank, the temperature in the washing tank is measured, and it is ensured that the temperature does not exceed a predetermined value. It is possible to reliably prevent the tableware from being deformed by heat.

  According to the present invention of claim 5, the second washing mode is performed by washing water in which a detergent containing bleach is dissolved before washing the dishes and before performing the sterilization step. You may further have the bleaching process for bleaching tableware.

  According to this, the low sterilization performance by low temperature washing | cleaning can ensure further sterilization performance by the sterilization effect by a bleaching agent, and the sterilization effect by a sterilization process.

  According to the present invention described in claim 6, the second cleaning mode includes a detergent cleaning step in which the control means drives the cleaning pump to clean the dishes with cleaning water in which a cleaning agent is dissolved. The bleaching step of driving the washing pump to bleach the dishes with washing water in which the alkaline bleach-containing detergent is dissolved; and the control means stops the washing pump, A sterilization step of evaporating wash water in which the detergent containing the bleach is dissolved to sterilize and bleach the dishes.

  According to this, a bleaching component evaporates by heating the washing water containing an alkaline bleaching agent, and the disinfection performance by a hot alkali can be ensured. Therefore, in addition to ensuring sterilization performance associated with higher temperatures, sterilization performance by a hot alkali component can be expected, and safe and considerably high sterilization performance can be ensured even for low temperature heat resistant containers.

  According to the present invention of claim 7, the washing water temperature in the washing step is 50 degrees, the washing water temperature in the bleaching process is 55 degrees, and the washing water temperature in the sterilization process is 65 degrees.

  According to this, in the washing and bleaching process in which washing water is sprayed with a washing pump, washing is performed at a heat resistant temperature of 60 degrees or less, so that high washing ability is achieved while deformation is reliably suppressed against washing of a low temperature heat resistant container. It can be secured. On the other hand, in the sterilization process, the washing pump is stopped and the washing water is set to 65 degrees, so that the deformation due to the heat effect on the low temperature heat resistant container is suppressed and the decomposition of the alkaline bleaching agent is accelerated. Therefore, it is possible to expect a further sterilization effect by hot alkali.

  Hereinafter, a dishwasher according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing the internal structure of the dishwasher according to this embodiment.

  The dishwasher includes a washing tank 1, a hot water heater 2 for heating washing water stored in the washing tank 1, a dish basket 3 provided in the washing tank 1 for storing dishes for washing, and tableware. A rotary cleaning nozzle 4 and a fixed cleaning nozzle 6 for injecting cleaning water into the tableware stored in the basket 3, and a cleaning water which is provided at the lower part of the cleaning tank 1 and pumps cleaning water from the rotary cleaning nozzle 4 and the fixed cleaning nozzle 6. Cleaning pump for injecting water, pump 5 functioning as a drainage pump for discharging cleaning water to the outside of cleaning tank 1, electromagnetic valve 7 for supplying cleaning water to cleaning tank 1, and cleaning tank The water level detection means 8 for detecting the water level of the cleaning water in 1, the blower fan 10 for sending air into the wash tank 1, the warm air heater 11 for warming the wind sent by the blow fan 10, and the temperature in the wash tank 1 Room temperature sensor 15 for detecting , A water temperature sensor 16 for detecting the temperature of the washing water, an exhaust port 12 provided on the front surface of the dishwasher for discharging the wind sent by the blower fan 10 to the outside of the machine, the pump 5, the electromagnetic valve 7, and the blower fan 10 And the control apparatus 13 which controls the warm air heater 11 grade | etc., And the operation panel 9 provided in the front surface of the dishwasher are provided.

  The dishwasher having the above-described configuration performs cleaning, rinsing and drying of the tableware stored in the tableware basket 3 in the cleaning tank 1. And the tableware washing machine concerning this embodiment is provided with a plurality of washing modes from which washing water temperature at the time of washing differs. That is, a standard cleaning mode in which cleaning is performed at a cleaning water temperature of about 70 to 80 ° C. and a low temperature cleaning mode in which the cleaning water temperature is lower than that in the standard cleaning mode are provided. The low-temperature cleaning mode is not suitable for high-temperature cleaning as in the standard cleaning mode, that is, suitable for cleaning plastic containers and dishes having a low heat-resistant temperature. Hereinafter, main features of the low temperature cleaning mode will be described while comparing the two cleaning modes.

  First, FIG. 2 is a time chart of the standard cleaning mode.

  In the standard cleaning mode, the cleaning process 21, the draining process 22 and the rinsing process 23 are performed in this order under the control of the control device 13.

  In the cleaning process 21, the hot water heater 2 operates to heat the cleaning water at a target temperature of 70 to 80 ° C. Further, in the cleaning step 21, the pump 5 operates as a cleaning pump.

  When the cleaning process 21 is completed, a drainage process 22 is performed in which the pump 5 operates as a drainage pump that discharges the cleaning water.

  In the rinsing step 23, as in the cleaning step 21, the hot water heater 2 performs an operation of heating the cleaning water so that the temperature becomes 70 to 80 ° C., and the pump 5 operates as a cleaning pump.

  FIG. 3 is a time chart of the low-temperature sterilization cleaning mode including a sterilization process for sterilizing tableware in the cleaning tank in the low-temperature cleaning mode.

  In the low temperature sterilization cleaning mode, the cleaning process 31, the sterilization process 32, the drainage process 33, and the rinsing process 34 are performed in this order under the control of the control device 13. That is, the low temperature cleaning mode and the standard cleaning mode described above are greatly different in that they have a sterilization step 32.

  In the cleaning step 21, the hot water heater 2 operates to heat the cleaning water at a target temperature of 60 ° C. or lower (55 ° C. in the figure), and the pump 5 operates as a cleaning pump.

  In the sterilization step 32, the hot water heater 2 and the blower fan 10 operate. The target temperature when the hot water heater 2 heats the cleaning water is 61 ° C. or higher and 70 ° C. or lower (65 ° C. in this embodiment). The hot water heater 2 is intermittently controlled based on the output of the water temperature sensor 16 so that the water temperature becomes constant at 65 ° C. while the water temperature is fed back based on the output of the water temperature sensor 16. In more detail about this point, since air has a smaller heat capacity than tableware, even if air heated to a high temperature comes into contact with tableware having a temperature lower than that of air, it is not possible to quickly raise the temperature of the tableware. On the contrary, when it comes into contact with the tableware, it is cooled to a temperature close to the tableware. Therefore, even if the tableware is controlled to come into contact with high-temperature air for a limited time, for example, about 30 minutes, the temperature of the tableware is increased so as to cause the tableware to be thermally deformed by the sterilization control. There is nothing. However, since the temperature is high until the air touches the surface of the tableware, a great effect can be expected for heat sterilizing the surface of the tableware.

  Here, although not shown, the blower fan 10 is driven in a drying step after the rinsing step and a ventilation step after the drying step, and is driven and controlled mainly for drying the tableware. Specifically, the blower fan is configured to be continuously driven for a predetermined time, about 1 hour in the drying process, or continuously at a lower rotation speed than the drying process for about 3 to 8 hours in the ventilation process. It is driven intermittently with a drive span that drives for about 10 minutes and rests for 1 minute so as to reduce the amount of rotation. In any case, it is equipped with a blowing capacity for the drying process and a ventilation process with a blowing capacity lower than that of the drying process.

  Further, in the present invention, a sequence for driving the blower fan in the sterilization process is provided, and the blower fan in the sterilization process performs intermittent operation lower than that in the drying process and the ventilation process. It is configured. The reason for this is that the driving of the blower fan in the sterilization process is not intended to release a large amount of humid air in the cleaning tank outside the cleaning tank, but the air in the cleaning tank is small and constant in the cleaning tank. This is because the main purpose is to create a flow. This air flow ensures that high temperature gas can be evenly touched to the tableware, and thus has the effect of ensuring high sterilization performance without unevenness. Furthermore, since the temperature distribution in the washing tank can be made uniform by this air flow, the absence of the low temperature portion can ensure the sterilization performance more evenly and, on the contrary, the high temperature portion above the predetermined level does not exist. Therefore, the heat effect on the low temperature heat resistant container such as plastic is suppressed, and the excellent effect that the deformation or the like of the tableware can be surely prevented is aimed at.

  Moreover, since intermittent control with the lowest blowing capacity of the blower fan is used, the power saving effect is great while achieving the above-mentioned purpose. In addition, since the airflow is not strong and gentle, high-temperature air does not intensively collide with the low-temperature heat-resistant container. As a result, the dishwasher according to the present embodiment has an excellent practical effect that it is possible to safely sterilize the low-temperature heat-resistant container. Here, the interval control is performed with a very wide interval such as driving for about 10 seconds and resting for several minutes.

  In this sterilization step 32, the pump 5 does not operate. That is, in the sterilization step 32, sterilization by steam is performed by raising the cleaning water temperature without spraying the cleaning water on the tableware. As a result, when washing is performed at a water temperature of 55 ° C., the sterilization performance is not necessarily sufficient, but the sterilization performance is achieved because sterilization is performed with high-temperature air at 65 ° C. while suppressing the thermal effect on the low-temperature heat-resistant container. Can be strengthened. Furthermore, in order to ensure the sterilization performance only by washing, it is necessary to make the washing time longer than necessary. However, this sterilization step is not necessary.

  When the sterilization step 32 is completed, a drainage step 33 is performed in which the pump 5 operates as a drainage pump to discharge the wash water.

In the cleaning step 21,
In the rinsing step 34, the hot water heater 2 operates similarly to the cleaning step 31, heating the cleaning water at a target temperature of 60 ° C. or lower (55 ° C. in the figure), and the pump 5 operating as a cleaning pump.

  In the above-described embodiment, the control device 13 controls the cleaning water temperature to be a predetermined target temperature based on the output of the water temperature sensor 16. However, as another embodiment, the control device 13 controls the room temperature sensor 15. Based on the output, the internal temperature may be controlled to be a predetermined target temperature, which is a more preferable mode. In the sterilization process, in order to reliably prevent thermal deformation of low temperature heat resistant containers such as plastic, the room temperature in the washing tank is measured and the atmosphere temperature in the washing tank is reliably set to a target temperature of 65 degrees. It is because it is more preferable to do. In other words, compared to the thermal effect of high-pressure injection of high-temperature liquid, the thermal effect can be suppressed to a small value because it only touches the low-temperature heat-resistant container with high-temperature air, but the air in the cleaning tank still exceeds the predetermined value. This is because it is not preferable to raise the temperature, which causes deformation of the container and the like, and it can be said that it is safest to perform feedback control so that the target room temperature is accurately set by room temperature control.

  Next, FIGS. 4 to 6 show process charts of cleaning modes of the dishwasher according to the present embodiment.

  FIG. 4A is a process chart of the above-described standard cleaning mode. Naturally, since the cleaning temperature is as high as 70 ° C., the sterilization performance is sufficient, and therefore no special sterilization process is necessary and is not set.

  As shown in FIG. 5A, in the standard cleaning mode, cleaning is performed with a detergent in the cleaning step 21, and then the drainage 22 and the rinsing step 23 are performed.

  FIG. 5B shows a process table that does not include the sterilization process, which is the point of the present invention, although it is in the low temperature washing mode, and a process that does not perform the sterilization process can be selected and executed. . That is, in this low temperature cleaning mode, the waste water 33 and the rinsing process 34 are performed after the cleaning process 31 for cleaning with a detergent. Here, the washing water temperature in the detergent washing step 31 is set to 50 ° C. which does not affect the low temperature heat resistant container.

  FIG. 5 shows a cleaning mode in which bleaching cleaning using a detergent containing a bleaching agent is performed after cleaning with a detergent, and such a process can also be selected.

  In the standard bleaching cleaning mode shown in FIG. 4A, the cleaning process includes a detergent cleaning process 21 and a bleaching cleaning process 25. When washing with a normal detergent is completed, a detergent containing a bleaching agent is put into the dishwasher, and bleaching washing is performed. The washing water temperature at the time of detergent washing and bleaching washing is 70 ° C., and no special sterilization process is required. Therefore, the sterilization process is not executed even in this mode.

  The low temperature bleach washing mode shown in FIG. 5B is also a mode including a detergent washing step 31 and a bleach washing step 35 in the washing step. The washing water temperature for the detergent washing is 50 ° C., and the washing water temperature for the bleach washing. Is 55 ° C. Even in this mode, the sterilization performance is not sufficient because the washing water temperature is low, but such a mode in which the sterilization process is not executed can also be selected. This mode can be said to be effective when it is necessary to complete the process quickly when it is dirty to the extent that sterilization is not necessary.

  FIG. 6 shows a process chart of a low temperature sterilization washing mode including a sterilization process which is a point of the present invention.

  The process chart of FIG. 6A corresponds to the time chart of the low temperature sterilization cleaning mode (low temperature steam sterilization cleaning) shown in FIG. That is, in the cleaning process 31, after washing with a detergent, the process proceeds to a sterilization process 32 in which sterilization with steam is performed. At this time, the washing water temperature in the washing step 31 is 50 ° C., and the washing water temperature in the steam sterilization step 32 is 65 ° C. Thereby, even if it does not wash | clean with high temperature washing water, it can sterilize reliably with high temperature steam, suppressing the heat influence to a low temperature heat-resistant container.

  FIG. 5B is a process chart of a low temperature sterilization cleaning mode (low temperature high power sterilization cleaning) including a bleach cleaning process. That is, the cleaning process 31 includes a cleaning process 31 using a detergent and a bleaching cleaning process 35 using a detergent containing a bleaching agent. After the bleach washing step 35, the process proceeds to a sterilization step 36 using washing water in which bleaching washing water is dissolved. In the sterilization step 36, the washing water is heated to 65 ° C. At this temperature, decomposition of the bleaching agent dissolved in the washing water is accelerated, and the active ingredient of the bleaching agent fills the chamber together with steam. This bleaching agent is an alkaline oxygen bleaching agent. Therefore, it becomes a hot alkali when the bleaching agent component is decomposed, and the sterilization performance can be dramatically improved.

  As mentioned above, by allowing the sterilization process to be performed as needed in the low temperature cleaning mode, it is not necessary to make the cleaning time longer than the time required for dishwashing for sterilization purposes, yet High sterilization performance can be ensured. Further, in the sterilization process, the cleaning water is not sprayed, and the temperature is raised by 10 ° C. or more to perform sterilization with steam or hot alkali. By increasing the temperature by 10 degrees, the sterilization performance is doubled. Therefore, the dishwasher according to the present embodiment can clean a plastic tableware having a low heat-resistant temperature without damaging it and perform low-temperature washing with high sterilization performance.

  The above-described embodiments of the present invention are examples for explaining the present invention, and are not intended to limit the scope of the present invention only to those embodiments. Those skilled in the art can implement the present invention in various other modes without departing from the gist of the present invention.

It is a figure which shows the internal structure figure of the dishwasher which concerns on one Embodiment of this invention. It is a time chart of standard washing mode. It is a time chart of low temperature washing mode. The process table | surface of standard washing | cleaning and a low temperature washing mode is shown. The process table | surface of a standard bleach washing | cleaning and a low temperature bleach washing | cleaning mode is shown. The process table | surface of the low temperature steam sanitization and the low temperature high power sanitization washing mode is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Washing tank 2 Hot water heater 3 Tableware basket 4 Rotating washing nozzle 5 Pump 6 Fixed washing nozzle 7 Solenoid valve 10 Blower fan 13 Control device 21 Washing process 22 Drainage process 23 Rinse process 31 Rinse process 32 Disinfection process 33 Drainage process 34 Rinse process

Claims (7)

In a dishwasher for washing, rinsing and drying stored dishes,
A washing tank for storing tableware,
Heating means for heating the washing water;
A cleaning pump for spraying cleaning water on the dishes;
A blower fan for discharging air in the cleaning tank;
Control means for controlling the heating means, the washing pump and the blower fan, and washing, rinsing and drying the dishes according to a predetermined washing mode;
The predetermined cleaning mode includes a first cleaning mode and a second cleaning mode in which the cleaning water temperature is lowered from the first cleaning mode,
In the second cleaning mode, after the dishes are cleaned, the control means stops the operation of the cleaning pump, and then the heating means is heated so that the temperature of the cleaning water rises to a predetermined temperature. A dishwasher comprising a sterilization step for sterilizing the tableware.   The blower fan is provided with at least a plurality of blowing characteristics of operation characteristics, and in the sterilization step, the control means is configured to perform intermittent operation with low blowing ability by the blower fan. The dishwasher according to claim 1. In the second cleaning mode,
The washing water temperature when washing the dishes is 60 degrees or less,
The dishwasher according to claim 1, wherein the washing water temperature in the sterilization step is 61 degrees or more and 70 degrees or less.   2. The dish washing apparatus according to claim 1, wherein, in the sterilization step, the control means controls the heating means for heating the washing water so that the air in the washing tank has a predetermined temperature or less. Machine.   The second washing mode further includes a bleaching step for bleaching the dishes with washing water in which a detergent containing a bleaching agent is dissolved before washing the dishes and before performing the sterilization process. The dishwasher according to claim 1, further comprising: The second cleaning mode is:
A detergent cleaning step in which the control means drives the cleaning pump to clean the dishes with cleaning water in which a cleaning agent is dissolved;
A bleaching washing step in which the control means drives the washing pump to perform bleaching washing of the dishes with washing water in which an alkaline bleaching detergent is dissolved;
6. The sterilization step in which the control means stops the cleaning pump and evaporates cleaning water in which the bleach-containing cleaning agent is dissolved to perform sterilization bleaching of the dishes. The dishwasher described.   The dishwasher according to claim 6, wherein the washing water temperature in the washing step is 50 degrees, the washing water temperature in the bleaching step is 55 degrees, and the washing water temperature in the sterilization step is 65 degrees.

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